/****************************************************************************
 **
 ** Copyright (C) Qxt Foundation. Some rights reserved.
 **
 ** This file is part of the QxtGui module of the Qxt library.
 **
 ** This library is free software; you can redistribute it and/or modify it
 ** under the terms of the Common Public License, version 1.0, as published
 ** by IBM, and/or under the terms of the GNU Lesser General Public License,
 ** version 2.1, as published by the Free Software Foundation.
 **
 ** This file is provided "AS IS", without WARRANTIES OR CONDITIONS OF ANY
 ** KIND, EITHER EXPRESS OR IMPLIED INCLUDING, WITHOUT LIMITATION, ANY
 ** WARRANTIES OR CONDITIONS OF TITLE, NON-INFRINGEMENT, MERCHANTABILITY OR
 ** FITNESS FOR A PARTICULAR PURPOSE.
 **
 ** You should have received a copy of the CPL and the LGPL along with this
 ** file. See the LICENSE file and the cpl1.0.txt/lgpl-2.1.txt files
 ** included with the source distribution for more information.
 ** If you did not receive a copy of the licenses, contact the Qxt Foundation.
 **
 ** <http://libqxt.org>  <foundation@libqxt.org>
 **
 ****************************************************************************/
#include "qxtglobalshortcut_p.h"
#include <QX11Info>
#include <X11/Xlib.h>

static int (*original_x_errhandler)(Display* display, XErrorEvent* event);

static int qxt_x_errhandler(Display* display, XErrorEvent *event)
{
	Q_UNUSED(display);
	switch (event->error_code)
	{
		case BadAccess:
		case BadValue:
		case BadWindow:
			if (event->request_code == 33 /* X_GrabKey */ ||
					event->request_code == 34 /* X_UngrabKey */)
			{
				QxtGlobalShortcutPrivate::error = true;
				//TODO:
				//char errstr[256];
				//XGetErrorText(dpy, err->error_code, errstr, 256);
			}
		default:
			return 0;
	}
}

bool QxtGlobalShortcutPrivate::eventFilter(void* message)
{
	XEvent* event = static_cast<XEvent*>(message);
	if (event->type == KeyPress)
	{
		XKeyEvent* key = (XKeyEvent*) event;
		activateShortcut(key->keycode, 
				// Mod1Mask == Alt, Mod4Mask == Meta
				key->state & (ShiftMask | ControlMask | Mod1Mask | Mod4Mask));
	}
	return false;
}

quint32 QxtGlobalShortcutPrivate::nativeModifiers(Qt::KeyboardModifiers modifiers)
{
	// ShiftMask, LockMask, ControlMask, Mod1Mask, Mod2Mask, Mod3Mask, Mod4Mask, and Mod5Mask
	quint32 native = 0;
	if (modifiers & Qt::ShiftModifier)
		native |= ShiftMask;
	if (modifiers & Qt::ControlModifier)
		native |= ControlMask;
	if (modifiers & Qt::AltModifier)
		native |= Mod1Mask;
	// TODO: resolve these?
	//if (modifiers & Qt::MetaModifier)
	//if (modifiers & Qt::KeypadModifier)
	//if (modifiers & Qt::GroupSwitchModifier)
	return native;
}

quint32 QxtGlobalShortcutPrivate::nativeKeycode(Qt::Key key)
{
	Display* display = QX11Info::display();
	return XKeysymToKeycode(display, XStringToKeysym(QKeySequence(key).toString().toLatin1().data()));
}

bool QxtGlobalShortcutPrivate::registerShortcut(quint32 nativeKey, quint32 nativeMods)
{
	Display* display = QX11Info::display();
	Window window = QX11Info::appRootWindow();
	Bool owner = True;
	int pointer = GrabModeAsync;
	int keyboard = GrabModeAsync;
	error = false;
	original_x_errhandler = XSetErrorHandler(qxt_x_errhandler);
	XGrabKey(display, nativeKey, nativeMods, window, owner, pointer, keyboard);
	XGrabKey(display, nativeKey, nativeMods | Mod2Mask, window, owner, pointer, keyboard); // allow numlock
	XSync(display, False);
	XSetErrorHandler(original_x_errhandler);
	return !error;
}

bool QxtGlobalShortcutPrivate::unregisterShortcut(quint32 nativeKey, quint32 nativeMods)
{
	Display* display = QX11Info::display();
	Window window = QX11Info::appRootWindow();
	error = false;
	original_x_errhandler = XSetErrorHandler(qxt_x_errhandler);
	XUngrabKey(display, nativeKey, nativeMods, window);
	XUngrabKey(display, nativeKey, nativeMods | Mod2Mask, window); // allow numlock
	XSync(display, False);
	XSetErrorHandler(original_x_errhandler);
	return !error;
}
